Why can't my M3 CS open the exhaust valve before starting anymore?

[Maitre_Absolut]

Originally Posted by Andrae26

Well that's not the case with my CS. The valves are open all the time in sport+ even if I'm not on the throttle cruising at low speed or high speed on the highway. Maybe because I have the MPE.

Originally Posted by melvyn

Mine is same as yours.

You can't tell unless you have a valve controller. There is no "my CS is different than yours"

[Andrae26]

Originally Posted by Maitre_Absolut

You can't tell unless you have a valve controller. There is no "my CS is different than yours"

Do you have the MPE? If not, then maybe that's why yours doesn't do it. 3 people on here have confirmed that their valves are always open with MPE and don't need a valve controller to do so. No one is saying their CS is different, we are just giving you straight facts. This is my 4th F80 and all of them had MPE so I'm sure I know what I'm saying is correct.

[melvyn]

It doesnt matter what exhaust you have, the CS valves are open all the time in Sport Plus and Sport.If they were not, you would not get any burbles coming off throttle, efficient no burbles, valves closed.

[depaulhifi]

Sorry all, been away from this thread a bit, obvi. Most of what is below is what I've found; the valves open immediately (you can clearly hear them open and close with the engine off) upon turning the ignition on, and based on the cacophony of noise in the garage after hitting the start button, I think they stay open for at least a minute after startup. The (non-) issue with not being able to switch modes after turning the ignition on was one related to timing. I found that you can't switch modes for the first 15 seconds or so after turning the ignition on.

Originally Posted by Andrae26

The CS starts with the valves open all the time. It's not like the other cars where you had to put it on sport and tap the gas to hear the valves opening and closing.

Originally Posted by melvyn

My experience is that the CS starts brieftly with vaves open which gives it the quick roar, then will close and wont open in S and S Plus untill cold start cycle has just about finished, even with the Awron set to valves open, they wont for about 10 secs.

Originally Posted by Maitre_Absolut

Not true

Buy a valve controller and you will see when the valves are open / closed.

On startup they are only open for the 2 second roar, then they close. I can immediately open them up again but not after they have initially closed.

In Sport+ they are still closed at low speeds, cruising on highway in higher gear, etc. There are many instances when they are closed.

I would not get rid of my valve controller, esp w AA mid.

Based on what I've experienced, I've found the valves are always open in Sport/Sport+ mode, regardless of how fast you're going. So far I've only driven at city speeds, maybe up to 35 mph and there is a night and day difference between valves closed (Efficient) and valves open (Sport/Sport+). Letting off the gas in D3, 2nd gear, from 30-some mph in Sport+ results in a massive amount of burbling from out back. Like the poster below, I too have MPE, so maybe that plays a part.

Originally Posted by Andrae26

Well that's not the case with my CS. The valves are open all the time in sport+ even if I'm not on the throttle cruising at low speed or high speed on the highway. Maybe because I have the MPE.

[LOW4LYF]

It's not related to the type of exhaust but could be related to the software version on the car.